If lines y=(2a-5)x-5 and 9y=(a+2)x-3 are perpendicular, what are all the possible values of a? Express your answers in decreasing order, separated by commas.

ILoveMySocks Apr 1, 2020

#1**+1 **

First put both equations in slope-intercept form to express the slope in terms of a.

Then multiply them together and set that product equal to -1 (The product of the slopes of two perpendicular lines is, for the most part, -1)

Then you solve for a using the quadratic formula or factoring.

Impasta Apr 1, 2020